FZRSupport: the FZROnline Archive

I am finishing a project bike based on an FZR400 chassis, with a yzf600r/fzr600 hybrid motor (the 660 mod), which is sitting under a YZF600 tank. Tuning with pods yields the expected hole in the midrange which is where I am most concerned with good torque.
My plan was to cut the base carb connection area out of a YZF airbox and mate it to a FZR400 box in order to fit inside both the frame and under the tank.
If there is a more elegant or simple solution please let me know. Any other suggestions would be welcomed.

When this engine was raced in AMA it made 112 RW HP with 55lb/ft torque when installed in a YZF chassis with stock airbox and supposedly pulled like a train from 5K, so I am trying to achieve this in a 50 lb lighter setup. It also has an R1 front end, Tuono race mini fairing and a Durbahn carbon subframe and tail section off an RC51, with a TZ250 swingarm and wheel, so should be fairly quick. The old FZR tank cover just didn't look right with the more modern tail, hence the YZF tank woes.

Thanks in advance guys

I just used the stock FZR400 air box and used the carb boots from the YZF600 - worked like a champ!

I had to cut larger holes to accommodate the boots, but that is all that I remember doing.

I might have given that air box to Nate... he might be selling it.

Maybe something similar to this can be useful to you?

viewtopic.php?f=30&t=3222 <---Click there

A flo commander solution would probably even out that midrange

Thanks for the above!

Has anyone tried the 96 pre-Ram Air airbox for the YZF600r in the fzr400 frame?

geekdoc wrote:Has anyone tried the 96 pre-Ram Air airbox for the YZF600r in the fzr400 frame?

I think it fits if I'm not mistaken as long as you're using the YZF tank.

How good is the Flo-Commander at improving the midrange jetting? That would make things a lot easier.

geekdoc wrote:How good is the Flo-Commander at improving the midrange jetting? That would make things a lot easier.

HOW-TO: Flo-Commander Tuning by ZERO9243 http://fzronline.com/wiki/doku.php?id=f ... der_tuning

the pre ram yzf airbox dosent fit into the 600 frame without large alteration dont know about the 400 though

So I guess I am looking for a FZR400 airbox, in case anyone in the US has a spare lying around.

As it turns out, an FZR600 airbox, lined up perfectly. The carb boot holes had to be dremeled out 1/8" to fit the larger YZF600r boots, after which it fir as if it we stock.
the airbox sat perfectly under the YZF tank as well.
The only issue now is mounting a Flo Commander inside, since the airbox screws together from the bottom, unlike most newer ones. I think I will be able to do it thru the filter hole after removing the snorkel, but it will be a bit of a ship in a bottle operation. Will post results.
Thanks for the ideas guys!

Hate to dig this up but I wanna get some details before I buy anything.

So to all that used an unmodified FZR400 airbox on a YZF600. Did you use the Fox Eye Tank (1994-1996) or the Thundercat one?